The Ben-my-Chree is likely to continue operating on one bow thruster until April next year.
The Steam Packet says while it's 'highly motivated' to replace the other damaged unit on the vessel, it has been badly let down by the manufacturer.
The company was responding to questions in the House of Keys about whether recent cancellations had been purely because of the strong winds, or also as the result of the damaged thruster.
The Ben has been operating with one bow thrust unit since the second one was damaged, and removed during an emergency dry-docking, earlier this year.
Steam Packet chief executive Mark Woodward says, despite constant pressure, the manufacturer of the unit has twice failed to meet promised repair times, and planned dry dock slots and charters for freight vessels have had to be cancelled. The manufacturer now claims the unit won't be ready until the New Year.
In a statement Mr Woodward says: 'This is just as frustrating for us as it is for our customers.
'If sailings are cancelled passengers and customers are inconvenienced, the company loses money and using tugs increases costs'.
Mr Woodward says once the repaired bow thrust unit is ready the Ben can only be taken out of service when a replacement charter vessel is available. However, only a few such boats are suitable and they can't be booked until the company has a definite timeline for repairs.
Mr Woodward says he believes it is likely the Ben won't be fully repaired until its scheduled dry docking in April.
However, he remains confident the sailings which have been cancelled recently wouldn't have operated even if the Ben had both bow thrusters working.